<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>函数</title>
</head>
<body>
    <script>
        function fn(a,b){
            var x = a + b;
            console.log('加法计算');
            return x;
        }
        // fn(1,2);
        console.log(fn(1,2));
    </script>
</body>
</html>